FLUORO-DOPA pattern in Kleine Levin syndrome

Abstract

Kleine Levin syndrome (KLS) is a rare neurological disorder characterized by excessive sleep with or without associated symptoms such as hyperphagia, abnormal behavior, cognitive dysfunction. Symptoms are cyclical and usually affect adolescents. Onset of symptoms is usually rapid and may last for days or weeks. The exact cause of KLS is unknown though it shows features of affection of hypothalamus that controls sleep, appetite and body temperature. There have been reports of viral infections preceding KLS raising a possibility of autoimmune response. Presented here is a six years old patient who had features of KLS. The FDG PET CT scan revealed hypometabolism in the thalami quite characteristic of the entity. F-DOPA scan revealed physiologic expression of dopaminergic activity in the neostriatum. However, the over-expression of dopaminergic activity in the right basi-frontal cortex and medial temporal lobe was also noted. The nigrostriatal, mesocortical, mesolimbic, tuberomammillary pathways are known dopamine transmitters. This case report attempts to explain the reason for dopaminergic expression in these regions in KLS.